To answer your questions, I’d first (and always) recommend asking your dermatologist. He/She is the best person to diagnose your skin type and condition.
Many factors contribute to the formation of acne. Learning what could be the cause of your acne breakouts allows you to take the proper prescriptive medications with the right active ingredients. Also, your dermatologist can put you on the right skin care routine based solely on your skin type. Sometimes with acne medication (and other products), you may have to adjust the methodology. Application of skincare products and the recommendations you receive can vary a great deal from one person to another.